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Iron-incorporated ordered carbonaceous frameworks (OCFs) have been synthesized by the pyrolysis of iron porphyrin with ethynyl groups as polymerizable/carbonizable moieties at a temperature higher than 600 °C. The pyrolysis behavior is analyzed by thermogravimetry-differential thermal analysis-mass spectrometry, and the obtained carbon materials are characterized by X-ray diffraction, X-ray absorption fine structure, and high-angle annular dark-field scanning transmission electron microscopy. The introduction of ethynyl groups at the meta positions of the peripheral phenyl groups is essential for efficient cross-linking upon thermal polymerization. The thermally stable polymer thus obtained can be transformed into OCFs with high carbonization yield of 93 % at the subsequent carbonization. OCFs possess periodic structural regularity and porphyrin Fe-N4 coordination structure, and exhibit electrocatalysis for the conversion of CO2 into CO.

One of the challenging targets in materials synthesis is a direct conversion of molecular based crystalline substances into crystalline ordered carbonaceous frameworks (OCFs). Though we have discov...

We successfully prepared and crystallographically characterized the first intermolecular charge-transfer (CT)-based vapochromic compound, (EV)(H3O)2[Fe(CN)6] (1-Wet, EV2+: 1,1′-diethyl-4,4′-bipyridine-1,1′-diium), an ethyl viologen-containing CT salt. 1-Wet, which is purple in color, is transformed into a brown powder (1-Dry) upon exposure to methanol vapor, drying over silica gel, or heating; 1-Dry returns to 1-Wet upon exposure to water vapor. These color changes are induced by hydration and dehydration, and gravimetric analyses suggest that 1-Dry is the dehydrated form of 1-Wet, namely, (EV)(H)2[Fe(CN)6]. Interestingly, desorption of water molecules from the oxonium ions in 1-Wet produces isolated protons (H+) that remain in 1-Dry as counter cations. Powder X-ray crystal structure analysis of 1-Dry reveals the presence of very short contacts between the nitrogen atoms of adjacent [Fe(CN)6]4– anions in the crystal. The isolated protons are trapped between the nitrogen atoms of cyanido ligands to form ve...

A Series of [Fe-II(L)(2)](BF4)(2) compounds were structurally and physically characterized (L = 2,6-bis(2-methylthiazol-4-yl)pyridine). A crystal structure phase transformation from dihydtate compound 1 to anhydrous compound 3 through partially hydrated compounds 2 and 2' upon dehydration was found. Compounds 1 and 3 exhibited a gradual spin crossover (SCO) conversion, whereas compounds 2 and 2' demonstrated two-step and one-step abrupt SCO transitions, respectively. An X-ray single-crystal structural analysis revealed that one-dimensional and two-dimensional Fe cation networks linked by π stacking and sulfur-sulfur interactions. Were formed in 1 and 3, respectively. A thermodynamic analysis of the magnetic susceptibility for 1, 2', and 3 suggests that the enthalpy differences may govern SCO transition behaviors in the polymorphic compounds 2' and 3. A structural comparison between 1 and 3 indicates that the SCO behavior variations and crystal structure transformation in the present [Fe-II(L)(2)](BF4)(2) compounds can be interpreted by the relationship between the lattice enthalpies mainly arising froth Coulomb interactions between the Fe cations and BF4 anions as in typical ionic crystals.

Despite recent advances in the carbonization of organic crystalline solids like metal-organic frameworks or supramolecular frameworks, it has been challenging to convert crystalline organic solids into ordered carbonaceous frameworks. Herein, we report a route to attaining such ordered frameworks via the carbonization of an organic crystal of a Ni-containing cyclic porphyrin dimer (Ni2-CPDPy). This dimer comprises two Ni–porphyrins linked by two butadiyne (diacetylene) moieties through phenyl groups. The Ni2-CPDPy crystal is thermally converted into a crystalline covalent-organic framework at 581 K and is further converted into ordered carbonaceous frameworks equipped with electrical conductivity by subsequent carbonization at 873–1073 K. In addition, the porphyrin’s Ni–N4 unit is also well retained and embedded in the final framework. The resulting ordered carbonaceous frameworks exhibit an intermediate structure, between organic-based frameworks and carbon materials, with advantageous electrocatalysis. This principle enables the chemical molecular-level structural design of three-dimensional carbonaceous frameworks., Carbon-based materials are promising alternatives to noble metal catalysts, but their structures are typically disordered and difficult to control. Here, the authors obtain ordered carbonaceous frameworks with advantageous electrocatalytic properties via the carbonization of nickel-containing porphyrin dimer networks.

A series of [Fe

The physicochemical properties of a series of the six-coordinated iron(III) diazaporphyrinate complexes, [Fe(DAzP)L2]± where the axial ligands (L) are DMAP, CN−, HIm, Py, 3-ClPy, 4-CNPy, 3-CNPy, 3,5-Cl2Py, THF, have been examined by combined analyses of NMR, EPR, Mossbauer spectrometry, and SQUID magnetometry. The solution and solid-state studies clarified that the complexes with 3-ClPy, 4-CNPy, 3-CNPy, 3,5-Cl2Py are in the less common spin-crossover process between S = 3/2 and S = 1/2 during the temperature change. The results clearly indicate that the complexes showed the switching behaviors of the electronic structure or the magnetic properties responsive to the external stimuli.

This review describes the switching behaviors of the electronic structure, which were observed in iron(III) porphyrinoids, by the addition of external stimuli. The combined analysis by various methods, such as EPR, Mossbauer, SQUID, single crystal X-ray structure analysis, revealed a wide variety of electronic structures of the heme related complexes. This paper focuses in particular on the spin-crossover phenomenon in the solid state. An overview of spin-crossover phenomena found in iron(III) porphyrinoids between (i) S = 5/2 and S = 1/2, (ii) S = 3/2 and S = 1/2, (iii) S = 5/2 and S = 3/2, will be described.

A tri-nuclear Co(II) complex of formula [Co3(phen)3(L1)2] [L1 = 2,2′,3,3′-tetrahydroxy-benzaldazine, phen = 1,10-phenanthroline] has been prepared. The complex was characterized by X-ray crystal analysis, ESI-MS and its UV–Vis spectrum. The room temperature value of χmT is 7.50 emu K mol− 1, which is larger than the expected value of 5.58 emu K mol− 1 (for three isolated high spin Co(II) ions). When the temperature is lowered the χmT product continuously decreases down to 5.0 K, which indicates the presence of antiferromagnetic coupling between the CoII ions.

We herein report the synthesis, single-crystal structures of coordination polymers, and structural transformations of complexes employing 1,4,5,6-tetrahydro-5,6-dioxo-2,3-pyrazinedicarbonitrile (tdpd2&minus, ) and pyrazine (pyz) as bridging ligands. {[M(H2O)4(pyz)][M(tdpd)2(pyz)]&middot, 6(H2O)}n, [1&middot, 10H2O and 2&middot, 10H2O where M = Co (1) and Zn (2)], consists of two types of crystallographically independent one-dimensional (1D) structures packed together. One motif, [M(tdpd)2(pyz)]2&minus, (A), is an anionic infinite pyz bridged 1D array with chelating tdpd2&minus, ligands, and the other motif is a cationic chain, [M(H2O)4(pyz)]2+ (B), which is decorated with four terminal water molecules. The 1D arrays (A) and (B) are arranged in parallel by multi-point hydrogen-bonding interactions in an alternate (A)(B)(A)(B) sequence extending along the c-axis. Both compounds exhibit structural transformations driven by thermal dehydration processes around 350 K to give partially dehydrated forms, 1&middot, 2H2O and 2&middot, 2H2O. The structural determination of the partially dehydrated form, 2&middot, 2H2O, reveals a solid-state structural transformation from a 1D chain structure to a two-dimensional (2D) coordination sheet structure, [Zn2(tdpd)2(H2O)2(pyz)]n (2&middot, 2H2O). Further heating to 500 K yields the anhydrous form 2. While the virgin samples of 1&middot, 10H2O crystallize in different crystal systems, powder X-ray diffraction (PXRD) measurements of the dehydrated forms, 1&middot, 2H2O, are indicative of the same structure. The structural transformation is irreversible for 1&middot, 10H2O at ambient conditions. On the other hand, compound 2&middot, 10H2O shows a reversible structural change. The solid-state structural transformation for 1&middot, 10H2O was also confirmed by monitoring in-situ magnetic susceptibility, which is consistent with other thermally-induced measurements.

Two novel 3D coordination polymeric networks based on Ag(I) and TTF derivatives, [Ag4(tces-TTF)2(CF3SO3)2](CF3SO3)2 (tces = 2,3,6,7-tetra(cyanoethylsulfanyl)) (1) and [Ag2(bmdt)2](SbF6)2 · acetone (bmdt = 4,5-bis(methylsulfanyl)-1,3-dithiole-2-thione) (2), were synthesized and crystallographically characterized. Both 1 and 2 have axially chiral helical motifs and these helices were assembled in a similar way: spiral up along b axis infinitely. In addition, complex 2 forms a “cds” network with a topology of 65.8. The conductivity of complex 1 was measured at RT with a σ value of 3.47 × 10−6S cm−1 due to the S⋯S contacts in the molecules, while 2 is an insulator at RT.

Reaction of the oligo(phenylenevinylene) 4,4′-bis(2,5-dimethylstyryl)biphenyl (bdb) with CF3CO2Ag in benzene gave a novel octanuclear sandwich cluster [Ag8(bdb)2(C6H6)2(CF3CO2)8]·2C6H6 (1). The clusters are packed on each other through strong π-π interactions to form 1D ′brick′ chains, between which the solvated benzene molecules are located. TG analysis showed that cluster 1 could completely liberate the guest benzene molecules at 105 °C and the coordinated benzene molecules at 180 °C. In solid state, cluster 1 exhibits fluorescence, and the emission band is red-shifted compared with that of free ligand bdb.

Four novel Mo(II) and Rh(II) complexes with cis-1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethene (cis-dbe) or closed-dbe were synthesized and characterized. Employing [M(O2CCF3)4] (M = Mo, Rh) with cis-dbe or closed-dbe afforded complex [Mo2(O2CCF3)4(cis-dbe)](benzene) (1), [Rh2(O2CCF3)4(cis-dbe)](benzene) (2), [{Mo2(O2CCF3)4}2(closed-dbe)] (3), and [Rh2(O2CCF3)4(closed-dbe)](p-xylene) (4). The structures of four metal complexes were revealed by X-ray crystallographic analyses and the correlation between the crystal structures and the photochromic performance was discussed. In all complexes, two cyano groups of the ligand bridged two dimetal carboxylates to give a 1-D zigzag infinite chain structure. Upon irradiation with 405 nm light, complex 1 turned into reddish purple from yellow, and the color reverted to initial yellow on exposure to 563 nm light, indicating the reversible cyclization/ring-opening reaction in the crystalline phase. However, the Rh(II) complex 2 did not display similarities in reaction induced by light, which is attributable to the lower ratio of photoactive anti-parallel conformers compared with complex 1 and coordination effect of metal ions on photochromism of diarylethenes. The complexes of Rh(II) ions did not exhibit the expected reversible photoinduced behavior.

Four novel mononuclear Rh–Cp* and Ir–Cp* complexes with polycyclic aromatic hydrocarbons (PAHs), [M(Cp*)(η6-PAHs)](BF4)2 (M = Rh and Ir; Cp* = η5-C5Me5; PAHs = phenanthrene (phn), pyrene (pyr) and triphenylene (triph)), were prepared by the reactions of the intermediate [M(Cp*)(Me2CO)3]2+ with appreciable PAHs. Their structures were characterized by a single crystal X-ray analysis, 1H, 13C {1H} NMR and 2D NMR techniques. The X-ray crystallographic studies showed that the [M(Cp*)]2+ fragment is η6-coordinated to one terminal benzene ring in each PAH. In particular, it is interesting to note that the partial π/π/π/π interaction was formed in the Ir–pyr complex [Ir(Cp*)(η6-pyr)](BF4)2. The 1D and 2D NMR studies described that the Rh–Cp* and Ir–Cp* complexes with PAHs gave unique 1H and 13C {1H} NMR spectra with positive coordination shifts (Δδ(1H, 13C)) in (CD3)2CO at 23 °C, which are likely induced by the local effect and the non-local effect on the coordination of the [M(Cp*)]2+ fragment to PAHs. The decreasing of the coupling constants (3JH–H) in the η6-coordinated benzene ring is also induced, with no changes in the uncoordinated benzene rings. The time-course of 1H NMR spectra showed that Rh–Cp* and Ir–Cp* complexes with PAHs are partially dissociated to [M(Cp*)(Me2CO)3]2+ and metal-free PAHs in (CD3)2CO at 23 °C. It was demonstrated that their stabilities are in the order of Ir–triph, Ir–phn, Ir–pyr and Rh–triph complexes in (CD3)2CO.

The preparation and physical characterization are reported for a family of novel Mn12 single-molecule magnets having diphenylphosphate (labeled dppH) bridges, [Mn12O12(O2CR)16 − x(dpp)x(H2O)y] (R = CH3: x = 4, y = 0 (1); x = 8, y = 2 (2), R = Ph: x = 4, y = 4 (5); x = 8, y = 4 (6), and R = Et: x = 4, y = 4 (9)) and their tetraphenylphosphate salts [Ph4P][Mn12O12(O2CR)16 − x(dpp)x(H2O)4] (R = CH3: x = 4 (3); x = 8 (4) and R = Ph: x = 4 (7); x = 8 (8)). The crystal structures of 1 and 5 were characterized by X-ray. The X-ray structure analysis of 1 reveals that there are four five-coordinate MnIII ions with Mn⋯H approaches and without coordinating water molecules. The 1H NMR measurements show H2O can coordinate to a vacant site of 1 in CD2Cl2 solution. Ac magnetic susceptibility measurements indicate that nine complexes are single-molecule magnets. The increase of the number of dpp− ligands resulted in a decrease of the Ueff values of neutral Mn12 SMMs estimated from ac measurements. Complexes 1 and 5 show a quantum tunneling behavior, whose ground states were tentatively assigned to S = 10 with g = 1.78, and D = −0.60 K; S = 10 with g = 1.92, and D = −0.63 K, respectively.

Reaction of the precursor Ir complex [Ir(H) 2 (PPh 3 ) 2 (Me 2 CO) 2 ]PF 6 with 3,6-bis(2-pyridyl)tetrazine (bptz) in CH 2 Cl 2 gave a novel dinuclear Ir hydrido complex [Ir 2 (H) 4 (PPh 3 ) 4 (bptz)](PF 6 ) 2 · 4CH 2 Cl 2 . Crystallographic study described an interesting coordination environment having a π–π interaction and 1 H NMR study showed unique upfield shifts of pyridyl rings that are likely induced by the ring current effect of neighboring PPh 3 ligands.

Coordination polymers of [2.2]paracyclophane (pcp) with in situ silver(I) perfluoro-dicarboxylates characterized by single crystal X-ray analysis are described. Structures are found to strongly depend on the dicarboxylate spacer (n). With disilver(I) tetrafluorosuccinate ((CF2)n(COOAg)2, n = 2), 3D network with composition of [Ag4(pcp)(C2F4(CO2)2)2] (1) forms in which silver salts afford infinite double chains and pcp act as linkages between chains. Changing the silver salt to disilver hexafluoroglutarate ((CF2)n(COOAg)2, n = 3) produces 3D pillared-layer structure of composition of [Ag4(pcp)(C3F6(CO2)2)2] · THF (2) (THF = tetrahydrofuran), in which silver salts form 2D sheets and pcp act as pillars between the sheets. With silver octafluoroadipate (HO2C(CF2)nCO2Ag, n = 4), 2-fold interpenetrated diamond structure, [Ag2(pcp)2(HO2CC4F8CO2)2]2 · 2toluene (3), is obtained in which silver-anion chains and silver-pcp chains are connected with each other in the perpendicular manner. The three complexes represent unprecedented metal-organic networks of silver(I) multicarboxylates and polycyclic aromatic compounds. Additionally, the effects of the dicarboxylate conformations as well as the solvents on the resulting structures were discussed.

Three luminescent silver(I)-oligo(phenylenevinylene) complexes, [Ag2(bmsb)(ClO4)2] (1), [Ag2(bmsb)(H2O)4](BF4)2 (2), and [Ag2(bdb)(CF3SO3)2] (3) (bmsb = 1, 4-bis(methylstyryl)benzene, bdb = 4,4'-bis(2, 5-dimethylstryryl)biphenyl), have been synthesized and structurally characterized. Complexes 1 and 2 are 2D networks with unique metallocyclophane motifs. Complex 3 affords a 2D zigzag sheet, in which silver triflates form tubelike double chains and bdb molecules act as linkages. Complex 2 exhibits high electric conductivity because of columnar aromatic stackings formed through intra- and intermolecular pi-pi interactions. Complexes 1-3 in the solid state exhibit luminescence, of which excitation and emission maxima are shifted to longer wavelength as compared to those of the corresponding metal-free ligands.

New five mono- and dinuclear Ir hydrido complexes with polydentate nitrogen ligands, [Ir(H) 2 (PPh 3 ) 2 (tptz)]PF 6 ( 1 ), [Ir 2 (H) 4 (PPh 3 ) 4 (tptz)](PF 6 ) 2 · 2H 2 O ( 2 · 2H 2 O), [Ir(H) 2 (PPh 3 ) 2 (tppz)]BF 4 ( 3 ), [Ir 2 (H) 4 (PPh 3 ) 4 (tppz)](BF 4 ) 2 ( 4 ) and [Ir 2 (H) 4 (PPh 3 ) 4 (bted)](BF 4 ) 2 · 6CHCl 3 ( 5 · 6CHCl 3 ), were systematically prepared by the reactions of the precursor Ir hydrido complex [Ir(H) 2 (PPh 3 ) 2 (Me 2 CO) 2 ]X (X=PF 6 and BF 4 ) with 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tptz), 2,3,5,6-tetrakis(2-pyridyl)pyrazine (tppz) and 1,4-bis(2,2 ′ :6 ′ ,2″-terpyridine-4 ′ -yl)benzene (bted), and their structures and properties were characterized in the solid state and in solution. Each of the Ir hydrido complexes with polydentate nitrogen ligands crystallographically described a unique coordination mode. Their 1 H NMR spectra demonstrated unusual 1 H NMR chemical shifts of pyridyl rings that are likely induced by the ring current effect of neighboring ligands.

Four copper(I) complexes of 2,11-dithia[3.3]paracyclophane (dtpcp), [CuI(dtpcp)] · MeCN (1), [CuBr(dtpcp)] · MeCN (2), [CuCl(dtpcp)] · MeCN (3) and [Cu2I2(dtpcp)2] · Me-thf (4) (Me-thf=2-methyltetrahydrofuran), have been synthesized and their molecular structures determined by X-ray crystallography. Complexes 1 and 2 are isostructural, and exhibit 3D networks with elliptical channels along a-axis, which are constructed by dtpcp molecules bridging zigzag CuI and CuBr chains, respectively. Complexes 3 and 4 are 2D porous sheet networks constructed by bridging the zigzag copper-dtpcp chains via rhombic ring of Cu2X2 (X=Cl or I). All sheets in 3 are packed in an eclipsed manner through π–π stackings to generate channels along the a-axis. However, the 2D porous sheets in 4 are packed in an offset mode such that channels are not formed along c-axis. Complexes 1 and 2 can reversibly incorporate guest acetonitriles without collapse of structures, and the original frameworks of 1 and 2 are completely recovered after incorporation of guests which are confirmed by X-ray powder diffraction (XRPD) pattern and 1H NMR spectrum. Additionally, complex 1 exhibits selectivity in size and polarity for guest inclusion.

Reaction of [2.2]paracyclophane (pcp) with silver(I) trifluoroacetate (AgCF(3)CO(2)) and silver(I) pentafluoroproprionate (AgC(2)F(5)CO(2)) has led to isolation of three novel intercalation polymers: [Ag(4)(pcp)(CF(3)CO(2))(4)](C(6)H(6)) (1), [Ag(4)(pcp)(CF(3)CO(2))(4)](C(6)H(3)Me(3)) (2), and [Ag(4)(pcp)(C(2)F(5)CO(2))(4)](pcp) (3). Structure studies using single crystal X-ray diffraction have shown that all compounds contain two-dimensional layered frameworks based on cation-pi interactions, in which pcp exhibits an unprecedented micro-tetra-eta(2) coordination mode. Guest molecules which weakly interact with the host pcp via C-H.pi interactions are intercalated between layers. The guest-eliminated complexes (1a and 2a) and guest-reincorporated ones (1b or 1c and 2b or 2c), accompanied by small structural changes, were confirmed by (1)H NMR, thermogravimetric analysis, mass spectra, and X-ray powder diffraction patterns. The structural changes from 1 --1a --1c (=1) can take place reversibly in the process of exposure of 1a to benzene vapor. The original framework of complex 2 is also completely recovered by immersing 2a in mesitylene as well as exposing it to mesitylene vapor.

The silver(I) complex of octakis(cyclohexylsulfanyl)-naphthalene (ochsn), [Ag4(ochsn)(CF3COO)4](CH2Cl2) (1), has been prepared and its molecular structure was determined by X-ray crystallography. In 1, the silver ion prefers a tetrahedral coordination geometry comprised of two S atoms from the ochsn molecules and the two O atoms from the counter anion then producing two-dimensional sheet structure. Interestingly, the naphthalene ring in the complex has large deviations from planarity and end-to-end twists on the order of 35°. In contrast, the central naphthalene ring of ochsn shows almost a planar structure in the solid state.

The preparation and physical characterization are reported for novel Mn12 single-molecule magnets having thiophenecarboxylate bridges, [Mn12O12(O2CC4H3S)16(H2O)4] (1), and its PPh4 salt (2). The reaction of the excess amount of 2-thiophenecarboxylic acid (tpcH) and [Mn12O12(OAc)16(H2O)4] in CH2Cl2 gave black crystals of 1, which could be reduced by PPh4I to give 2. From the crystal structure analysis of 2, it is revealed that there are two five-coordinated Mn ions, one of which is assigned to a MnII ion being in the vicinity of the tetraphenylphosphonium cation. Both complexes exhibit out-of-phase a.c. magnetic susceptibility (χ″M) signals in the 5.0–6.5 K range at 997 Hz a.c. frequency, which indicate that they are single-molecule magnets. From Arrhenius plots of the frequency dependence of the temperature of the χ″M peaks, the effective energy barriers Ueff were estimated to be 69 and 57 K for high-temperature phases of 1 and 2, respectively, and 40 K for the low-temperature phase of 1. The reduced magnetization measurement and its analysis indicate that 2 has S=19/2 ground state with g=1.99 and D=−0.61 K.

As a continuation of the study on the construction of the multidecker aromatic compounds with pi-pi interactions, the anthracene derivatives 9,10-dimethylanthracene (dman), 9,10-diphenylanthracene (dpan), and 7,12-dimethylbenz[a]anthracene (dmban) have been studied toward complexation with the silver(I) ion. The crystal structures of [Ag(dman)(0.5)(p-xylene)(ClO(4))], [Ag(2)(dpan)(0.5)(C(6)H(6))(0.5)(CF(3)SO(3))(2)], and [Ag(2)(dmban)(2)(ClO(4))(2)](p-xylene), together with the metal-free ligand dpan, have been determined by single-crystal X-ray diffraction. These pi-electron-rich aromatic compounds are found to have great promise as an approach to the effective self-assembly of high nuclearity in a multilayer fashion.

The silver(I) complex [Ag2(3bsb)2(ClO4)2] (1) (3bsb; 1,3,5-tris(benzylsulfanyl)benzene) has been prepared and its molecular structure was determined by X-ray crystallography. In 1, the silver ion prefers a tetrahedral coordination geometry and produces a two-dimensional sheet structure containing dimeric units. Irradiation of this complex 1 with light changes its color from white to pink; heat or exposure to acetone vapor makes the irradiated sample revert back to white. However, only 3bsb has no characteristic like this photochromism.

Five novel silver(I) coordination polymers with cis-1,2-dicyano-1,2-bis(2,4,5-trimethyl-3- thienyl)ethene (cis-dbe) were synthesized and are characterized in this paper. Treatment of AgCF(3)SO(3) or AgCF(3)CO(2) with cis-dbe afforded [Ag(2)(cis-dbe)(CF(3)SO(3))(2)] (1) and [Ag(2)(cis-dbe)(CF(3)CO(2))(2)] (2), and both complexes exhibit a 1-D infinite chain structure with two cyano groups and two thienyl groups of the ligand bridging four metal ions. Reaction of AgC(n)()F(2)(n)(+1)CO(2) with cis-dbe gave rise to an unprecedented cocrystallization of a 2-D sheet structure, [Ag(2)(cis-dbe)(C(n)F(2)(n)(+1)CO(2))(2)], where n = 2 (3), 3 (4), and 4 (5). Upon irradiation with 450 nm light, these five silver(I) complexes turned orange or red from yellow, and the color reverted to yellow on exposure to 560 nm light, indicative of the reversible cyclization/ring-opening reaction occurring in the crystalline phase. Furthermore, different anions gave not only the different structural dimensions but also the different photoresponsive patterns. The correlation between the crystal structures and the photochromic reactivity is discussed.

For the purpose of investigation on the reactivity of silver(I) with multiphenyl diene and the effect of counteranions on silver(I) complexes, we selected several silver(I) salts to react with trans , trans -1,4-diphenyl-1,3-butadiene (dpbd). The treatment of AgClO 4 ·H 2 O with dpbd afforded a 1-D W-type chain silver(I) coordination polymer [Ag(dpbd)(ClO 4 )] ( 1 ) and while the reaction of AgCF 3 CO 2 with dpbd gave rise to a co-crystallization structure [Ag 3 (CF 3 CO 2 ) 3 ]·(dpbd) ( 2 ) in which silver(I) and trifluoroacetate form a 1-D supramolecular ladder chain. The measurements of electric conductivity show that polymer 1 exhibits semiconductive behavior and while polymer 2 is an insulator. The effect of counteranions and steric hindrance on the formation of these silver(I) complexes is also discussed.

A novel silver(I) coordination polymer of 1-methylpyrene (mpyr) with double-decker motifs, {[Ag2(mpyr)2(ClO4)2]0.5benzene}n (1), was synthesized and characterized. Polymer 1 consists of 1-D double-decker chains, which are formed by dimeric double-decker units ([Ag(mpyr)(ClO4)]2) through the linkage of the perchlorate groups. In addition, the dimeric moieties between the adjacent chains are stacked to lead to column π−π stacks. Therefore, complex 1 can also be regarded as a 2-D stacking polymer. The effects of substituting groups, and other factors, on the structure of silver(I) complexes with polycyclic aromatic hydrocarbons are also discussed.

A novel 2-D silver(I) coordination polymer of 1,8-diphenylocta-1,3,5,7-tetraene was synthesized, and characterized by X-ray single crystal analysis. Reaction of 1,8-diphenylocta-1,3,5,7-tetraene (dpot) with silver(I) perchlorate at 60 °C afforded [Ag2(dpot)(ClO4)2]n (1). In this structure, silver(I) adopts a distorted tetrahedral geometry and the dpot molecules link the silver(I) ions in a trans-μ-tetra-η2 manner to generate 1-D chains with metallocyclophane motifs. Further, the silver(I) ions between the two neighboring chains are bridged by perchlorate groups to give a novel 2-D (3,4)-connected polymeric network with (4,62)2(42,62,82) topology. Additionally, the main plane of the phenyl moiety makes an angle of 33.08° with the topology through the polyene portion in 1, and thus the coordination of silver(I) to dpot results in the distortion of the dpot molecule. To the best of our knowledge, this is the first example of a silver(I) complex with acyclic polyene.

Three novel silver(I) complexes with benzopyrene derivatives were synthesized and characterized in this paper. Treatment of AgClO4•H2O with 7-methylbenzo[a]pyrene (L1) afforded [Ag2(L1)(toluene)0.5(ClO4)2]n (1) which exhibits a 2-D sheet structure with double-stranded helical motifs. Reaction of AgCF3SO3 with dibenzo[b,def ]chrysene (L2) gave rise to an unprecedented cocrystallization structure, {[Ag2(L2)(CF3SO3)2][Ag2(toluene)2(CF3SO3)2]}n (2), formed by a 2-D neutral lamellar polymer and a 1-D neutral rodlike one. The ligand benzo[e]pyrene (L3) coordinated to silver(I) ions generating a closed triple-decker tetranuclear complex [Ag4(L3)4(p-xylene)(ClO4)4] (3) which can be regarded as a stacking polymer owing to existing intermolecular π−π stack interactions. The structural diversity of the silver(I) coordination polymers with polycyclic aromatic hydrocarbons is not only related to the stacking patterns of free polycyclic aromatic hydrocarbons in the crystalline state, but also the geometric shapes of th...

Four copper(I) and six silver(I) novel co-ordination polymers linked by 1,4-bis(4-pyridyl)butadiyne (4-bpbd) or 1,4-bis(2-pyridyl)butadiyne (2-bpbd) were prepared and seven structures crystallographically characterized, in order to illustrate the structural versatility of co-ordination polymers assembled by the Group 11 metal ions and rod-like nitrogen bidentate ligands with long spacers. Reaction of appropriate copper(I) and silver(I) salts with the 4-bpbd ligand affords 2-D interwoven copper(I) co-ordination polymers {[Cu2(4-bpbd)3(CH3CN)2]X2}n (X = PF61a·2H2O or BF41b) and 1-D straight chain silver(I) co-ordination polymers {[Ag(4-bpbd)]X}n (X = NO32a·CH3CN, ClO42b·(CH3)2CO or CF3SO32c·(CH3)2CO), respectively. On the other hand, reaction of suitable salts with the 2-bpbd ligand provides a 3-D diamondoid copper(I) co-ordination polymer {[Cu(2-bpbd)2]BF4}n3b, a 1-D zigzag chain silver(I) co-ordination polymer {[Ag(2-bpbd)(NO3)]}n4a and a 2-D braid sheet silver(I) co-ordination polymer {[Ag(2-bpbd)(CF3SO3)]}n4c, respectively. On the basis of these structural studies, the unique structural features and the dimensionality of the copper(I) and silver(I) co-ordination polymers are revealed.

The title complex, [Ag4(C5F6O4)2(C14H8N2)(C4H8O)2]n, exhibits a one-dimensional chain structure propagated through inversion centres, with two crystallographically independent AgI atoms in the asymmetric unit. One of the Ag atoms has a distorted trigonal-pyramidal coordination, defined by two carboxyl O atoms from two hexafluoro­glutarate (HFG2−) anions, one N atom from 4,4′-biphenyl­dicarbonitrile and one apical O atom of tetrahydro­furan. The other Ag atom is coordinated by two O atoms from two HFG2− anions.

The title compound, {[Ag2(C16H16S2)2(C2H3N)4](C8F4O4)·2C8H2F4O4·4C2H3N}n, has been prepared from the reaction of 2,11-di­thia­[3.3]­paracyclo­phane (dtpcp) and in situ silver(I) tetrafluoroterephthalate (TFTP2−) using an interface method. In the solid state the title compound forms two infinite chains, which are parallel to one another. One chain consists of [Ag2(C16H16S2)2(C2H3N)4]n2n+, and the other is formed from TFTP2− and H2TFTP via Oc—H⋯Oc (c is carboxy) hydrogen- bonding interactions, with H⋯A distances of 1.72 (2) and 1.774 (19) A. The AgI ion is tetrahedrally coordinated by two aceto­nitrile N atoms and two dtpcp S atoms. The cyclo­phanes have inversion symmetry.

The title compound, [Mn2(mu-O)(C6H3NO3)2(C5H5N)4].H2O, was isolated from the reaction of 2,6-pyridinedicarboxylic acid with [Mn12O12(CH3COO)16(H2O)4] in pyridine. The dimanganese complex has twofold symmetry; the MnIII atoms are bridged by one oxo and two amidate ligands and show compressed octahedral Jahn-Teller distortion. The molecular packing comprises a three-dimensional structure constructed by means of extensive intermolecular interactions, including three kinds of hydrogen bonds and pi-pi interactions.

The title compound, {[Ag(C16H16S2)(C2H3N)2](C6HF8O4)}n, forms two infinite chains, which are approximately perpendicular to each other. One chain consists of [Ag(C16H16S2)(C2H3N)2]nn+, and the other is formed from HOFA− (HOFA− is hydrogen octa­fluoro­adipate) units via Oc—H⋯Oc (c is carboxy) hydrogen-bonding interactions, with an H⋯A distance of 1.66 (5) A. Each silver(I) cation lies on a crystallographic twofold rotation axis and has a tetrahedral geometry, defined by two N atoms belonging to two aceto­nitrile mol­ecules and two S atoms from two 2,11-di­thia­[3.3]­para­cyclo­phane mol­ecules. The cyclophanes have inversion symmetry.

The novel silver(I) coordination polymer with 2,5-bis(4‘,5‘-bis(methylthio)-1‘,3‘-dithiol-2‘ylidene)-1,3,4,6-tetrathiapentalene (TTM-TTP), [Ag(TTM-TTP)(CF3SO3)]n (1), which consists of 1-D waving chains, was synthesized and characterized. Polymer 1 can be also regarded as a 3-D supramolecular network formed via many shorter side-by-side and face-to-face S···S contacts. This polymer and its iodine-doped compound 2 behave as semiconductors with σ25°C values of 7.1 × 10-6 and 0.85 S cm-1, respectively.

Three novel Cu(I) metallacalixarenes with C(2)H(4) and CO legs, in which an anion is accommodated in the inside cavity, were self-assembled by anion templation and have been structurally characterized.

Reaction of [2.2]paracyclophane with silver(I) heptafluorobutyrate (AgC 3 F 7 CO 2 ) has isolated three novel networks: [Ag 4 (pcp)(C 3 F 7 CO 2 ) 4 ].pyrene (1), [Ag 4 (pcp)(C 3 F 7 CO 2 ) 4 ].phen (phen = phenanthrene) (2), and [Ag 4 (Pcp)(C 3 F 7 CO 2 ) 4 ]. fluorene (3), and an intercalation compound [Ag 4 (Pcp)(C 3 F 7 CO 2 ) 4 ].2benzene (4). All the four complexes exhibit two-dimensional (2D) sheet structures in which AgC 3 F 7 CO 2 form an infinite chain and pcp acts as linkage. 1, 2, and 3 show 2D flat sheets with cavities in which guest molecules are situated, whereas 4 exhibits 2D zigzag layers between which guest benzene molecules are intercalated. Pcp shows μ-di-η 1 -η 2 coordination mode in 1, μ-tetra-η 1 coordination mode in 2 and 3, and μ-tetra-η 2 coordination mode in 4. The reversible guest exchanges were observed between complex 1, 2, or 3 and intercalation compound 4. It is unprecedented for metal-organic inclusion complexes that the guest exchange occurs where the guest is the solute molecule. Furthermore, 4 can release the guest, and the original framework was completely recovered after reincorporation of benzene. It should be noted that 4 can incorporate pyrene, phen, and fluorene to give 1, 2, and 3, respectively, after desorption.

In the title complex, [Ag 2 (C 7 H 4 NO 4 ) 2 (C 16 H 16 S 2 )], each Ag I atom is trigonally coordinated by one S atom of a 2,11-dithia[3.3]paracyclophane (dtpcp) ligand, and by one N and one O atom of a 6-carboxypyridine-2-carboxylate ligand. Dtpcp acts as a bidentate ligand, bridging two inversion-related Ag I atoms to give a dinuclear silver(I) compound. The dinuclear moieties are interconnected via O-H...O hydrogen bonds to form a two-dimensional zigzag sheet. Two such sheets are interwoven via π-π interactions between pyridine rings, affording an interwoven bilayer network.

The preparation and physical characterization are reported for a novel single-molecule magnet [Mn(12)O(12)(OAc)(12)(dpp)(4)] (dppH = diphenyl phosphate) with no coordinating water molecules. The crystal structure analysis reveals that there are four five-coordinate Mn(III) ions with Mn.H approaches. Addition of water in CD(2)Cl(2) solution was monitored by (1)H NMR, which showed that H(2)O could coordinate to a vacant site of a five-coordinate Mn(III) ion in solution. The measurements and analyses of magnetization hysteresis and ac magnetic susceptibility indicate that the title complex is a single-molecule magnet with a quantum tunneling behavior, whose ground state was tentatively assigned to S = 10 with g = 1.78 and D = -0.60 K.

A novel 3-D silver(I) cationic coordination polymeric network, [Ag4(bcdt)4(CF3SO3)2]·(CF3SO3)2·acetone (bcdt = 4,5-bis(cyanoethylsulfanyl)-1,3-dithiole-2-thione) with double (3,4)-connected nodes a...